Controlling apparatus for highway crossing signals



6,1937. H. c. VANTASSEL 2,071,052.

CONTROLLING APPARATUS FOR HIGHWAY CROSSING. SIGNALS 7 Filed April 10, 1955 INVENTO'R Harry C. Vcmfassel Mag,

I m5 ATTORNEY Patented Feb. 16, 1937 UNITED STATES PATENT OFFIE CONTROLLING APPARATUS FOR HIGHWAY CROSSING SIGNALS Application April 10, 1935, Serial No. 15,634

8 Claims.

My invention relates to controlling apparatus for highway crossing signals, that is, tomeans for the control of signals which are placed at intersections of railways and highways for the purpose of warning users of the highway when a train is approaching.

One feature of my invention is the provision of means which will control a highway crossing signal for a track on which trains move in both 10 directions in such a manner as to stop the operation of the signal after it has been initiated by an approaching train if such train consumes more than a predetermined time interval in approaching the crossing, and which also will again initiate the operation of the signal if the train subsequently approaches the crossing.

I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view illustrating one form of apparatus embodying my invention.

Referring to the drawing, the rails I and IA of a stretch of railway track X are divided by insulated joints 2 into relatively long sections AB and 0-D, which are separated from each other by a relatively short section BC. Section B-C includes the intersection of the rail- Way and a highway designated by the reference 30 character H. Each section is provided with a track circuit including a track relay designated by the reference character R with a distinguishing suffix connected across the rails I and IA at one end of the section, and a track battery 3 connected across the rails at the other end of the section. The highway crossing H is protected by a signal S of any suitable type such, for example, as a bell or a light signal or a combination of both, which signal is controlled by a signal control relay designated by the reference character K The sections AB and C-D usually will be of such length as to provide adequate warning at the crossing for trains traveling at normal speed, and section B-C usually will be of such length as to provide adequate warning for trains traveling at slow speed.

Associated with each track relay RI and R3 is a stick relay designated by the reference character P with the same suffix as that used in the reference character for the associated track relay.

Associated with each stick relay PI and P3 is a timing device, here shown as a thermal relay,

and designated by the reference character T with a suitable distinguishing suffix.

As will be explained hereinafter, the stick relays PI and P3 are effective to prevent operation of the crossing signal by the relays RI and R3 when the sections AB and CD become occupied by trains receding from the crossing and also are effective in conjunction with the associated thermal relays for discontinuing the operation of the signal if a train moving towards the crossing consumes more than a measured interval of time in the initial control section.

The reference character 4 designates a source of energy which is here shown as a battery.

Each of the thermal relays TI and T3 is provided with contacts Ill and I 4, respectively, which are closed only when the associated relay is in its initial or deenergized condition, and with contacts I2 and I6, respectively, which are closed only when the associated relay attains its operated condition a.- predetermined time interval after energy is applied to heating elements I! and I8, respectively.

The signal 3 is control1ed only by a back contact 5 of relay K. Signal S, therefore, will be operated when relay K is released and back contact 5 becomes closed.

The signal control relay K is provided with a main control circuit and two auxiliary circuits. The main control circuit passes from battery 4 through front contact II of relay RI, front contact I5 of relay R3, front contact 6 of relay R2 and relay K to battery 4. The first auxiliary circuit passes from battery 4 through contact I0 of relay TI, front contact I of relay PI and thence over front contact I5 of relay R3 and the same path just traced for the main control circuit. The second auxiliary circuit passes from battery 4 through front contact II of relay RI, front contact 2| of relay P3, contact I4 of relay T3 and thence over front contact 6 of relay R2 and the same path just traced for the main control circuit. Signal control relay K, therefore, will become released at all times when relay R2 is released, and also will become released when relays RI or R3 become released provided the associated stick relays are in their normal deenergized condition.

The thermal relay TI is provided with a circuit which passes from battery 4 through back contact 9 of track relay RI, the back point of contact 6 of relay PI and heating element I! of relay TI to battery 4. Likewise, the thermal relay T3 is provided with a circuit which passes from battery 4 through back contact I3 of track relay R3, the back point of contact 8 of relay P3 and heating element l8 of relay T3 to battery 4. Relays TI and T3, therefore, will become energized when relays R! and R3, respectively, become released provided the associated stick relays are in their normal deenergized condition.

Each stick relay PI and P3 is provided with two pick-up circuits and one stick circuit. The first pick-up circuit for relay Pl passes from battery 4 through back contact iii of relay R2 and relay Pl to battery 4. The second pick-up circuit for relay Pl passes from battery 4 through contact l2 of thermal relay TI and relay Pl to battery 4. The stick circuit for relay Pl passes from battery 4 through back contact 9 of relay RI, front point of contact 6 of relay. PI and relay PI to battery 4. The first pick-up circuit for relay P3 passes from battery 4 through back contact 20 of relay R2 and relay P3 to battery 4. The second pick-up circuit for relay P3 passes from battery 4 through contact 16 of thermal relay T3 and relay P3 to battery 4. The stick circuit for relay P3 passes from battery l through back contact I 3 of relay R3, front point of contact 8 of relay P3 and relay P3 to battery 4. The stick relays Pi and P3, therefore, will become energized when track relay R2 is released or when the associated thermal relay is in its operated condition, and upon being energized will be maintained in their energized positions when the track relays RI and R3, respectively, are released.

Having thus described the various parts of the apparatus embodying my invention, I will now explain their operation.

Under normal conditions, the track relays RI, R2, and R3 are all energized and the stick relays PI and P3, as well as the thermal relays TI and T3 are all deenergized. I shall now assume that an eastbound train, that is, a train moving toward the right as shown in the drawing, enters section AB and causes the deenergization of track relay Rl. This opens front contact I l of relay RI which interrupts the main control circuit for the signal control relay K. The deenergization of relay K establishes the signal operating circuit passing through back contact 5 of relay K, thereby causing the signal S to give warning to traffic on the highway H of the approaching train.

I shall next assume that the train stops in section A--B. For example, the train may stop to discharge or receive either passengers or freight. The deenergization of track relay RA, in addition to initiating the operation of the signal S, will also, through the closing of its back contact a, establish a circuit over the back point of contact 6 of relay Pl for heating element ll of thermal relay Tl. As soon as heating element H begins to heat checking contact It Will become opened and will not become closed again until heating element l1 cools after energy is disconnected. At the expiration of a given time interval when relay Tl has attained its operated condition contact [2 will become closed. When contact I2 is closed stick relay PI becomes energized so that energy is disconnected from heating element ll. As soon as heating element I! cools so that checking contact IO recloses, an auxiliary circuit for relay K, including front contact '1 of relay PI and checking contact Ill, becomes closed thus energizing signal control relay K so that signal S ceases operation. From the foregoing description, it is readily apparent that thermal'relay Tl must go through a complete cycle of energization and subsequent deenergization in order to interrupt the operation of signal S when the signal is operating due to the occupancy of section AB. That is, energy must be applied to heating element ll, contact I: must close to energize the stick relay so that energy will be removed from heating element I7, and the heating element I! must cool to permit the reclosing of checking contact H3. Usually, the relay Tl will be so adjusted that its complete cycle of operation cannot take place during the time required for a train traveling at normal speed to traverse section AB. The operation of signal S, therefore, will not be discontinued for trains traversing section A--B at normal speed but only in the event such trains stop or otherwise consume in section AB an interval of time greater than the total operating time of thermal relay T2.

I shall next assume that the train again proceeds towards the crossing and enters section BC, thus releasing track relay R2. Since the main circuit for the control of relay K includes front contact 6 of relay Rl2,'the signal S will again operate to warn highway trafic of the approach ing train and will continue to operate as long as section BC is occupied. The releasing of relay R2 will close its back contact 20 so that a pickup circuit of relay P3 is established. When relay PS picks up, the auxiliary circuit around front contact I5 of relay R3 is closed so that, when the train enters section CD and front contact It: becomes opened, the relay K will not become deenergized. The stick circuit for relay P3, including the front point of its own contact 8, will be closed when back contact iii of track relay R3 becomes closed so that relay P3 will remain energized while the train is traversing section C-D. The signal S, therefore, is prevented from operating while the train is receding from the crossing although track relay R3 is released.

While I have not described the operation of the apparatus embodying my invention for a westbound train, it will be seen from the foregoing description that the apparatus functions in a manner similar to that just described for an eastbound train.

Although I have shown apparatus embodying my invention applied to a single track, it is readily apparent to those skilled in the art that, if desired, the relay K may be controlled from more than one track by apparatus exactly similar to that shown for track X.

The apparatus embodying my invention, therefore, provides a simple and reliable means for operating a highway crossing signal in which excessive operation of the signal is prevented in the event that an approaching train initiates the operation of the signal and then does not proceed immediately over the crossing. Furthermore, my invention provides for a second operation of the signal when such train subsequently approaches the crossing.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be'made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invent-ion, what I claim is:

1. In combination, a stretch of railway track intersected by a highway, a signal for controlling traflic over said highway at such intersection, means eifective to initiate the operation of said signal when railway traffic moving towards the intersection occupies certain zones, means effective to discontinue the operation of said signal a measured time interval after such initiation, and means effective to cause the operation of said'signal when railway trafiic moving in either directionoccupies a particular zone adjacent the intersection.

2. In combination, a stretch of railway track divided into a first section and a third section separated from each other by a second section intersected by a highway, a signal for controlling trafiic over said highway at such intersection, a signal control relay, a first track relay associated with said first section for controlling said signal control relay, a second track relay associated with said second section for controlling said signal control relay, a third track relay associated with said third section for controlling said signal control relay, means for causing said first and said third track relays to be effective for controlling said signal control relay for traflic moving only towards said highway, and means for removing said signal control relay from control by said first and third track relays a predetermined time interval after such track relays become effective for controlling said signal control relay.

3. In combination, a stretch of railway track divided into a first section and a second section separated from said first section by another section intersected by a highway, a signal for controlling traffic over said highway at such intersection, a first track relay associated with said first section for controlling said signal for railway traific moving over said stretch in one direction, a second track relay associated with said second section for controlling said signal for rail- Way traffic moving over said stretch in an opposite direction, another track relay associated with said other section for controlling said signal for railway traffic moving over said stretch in either direction, two thermal relays one associated with each of said first and second sections, two stick relays one associated with each of said first and second sections, means responsive to trafiic conditions in said first and said other section for controlling the thermal relay and the stick relay associated with the first section, and means responsive to traflic conditions in said second and said other section for controlling the thermal relay and the stick relay associated with the second section.

4. In combination, a stretch of railway track divided into three sections, a track relay for each section, two thermal relays one associated with each of two of said track relays, two stick relays one associated with each of such two track relays, a signal, a signal control relay, a first circuit for said signal control relay including a front contact of each track relay, a second circuit for said signal control relay including a contact of the thermal relay and a front contact of the stick relay associated with one of said track relays, and a third circuit for said signal control relay including a contact of the thermal relay and a front contact of the stick relay associated with the other of said track relays.

5. In combination, a stretch of railway track including an intersection with a highway, a first track section and a second track section included in said stretch and successively occupied by a train approaching said intersection, a highway crossing signal located at said intersection, a normally energized signal control relay effective when deenergized to cause the operation of said signal, a track circuit including a track relay for each section," means governed by the track relay for the first section effective to 'deene'rgize said signal H control relay when such track relay becomes released by a train approaching the intersection, means effective to energize said signal control relay a predetermined time interval after the release of the track relay for the first section, and means governed by the track relay for the second section for again deenergizing said signal control relay when such track relay becomes released.

6. In combination, a stretch of railway track including an intersection with a highway, a first track section and a second track section included in said stretch and successively occupied by a train approaching said intersection, a highway crossing signal located at said intersection, a normally energized signal control relay effective when deenergized to cause the operation of said signal, a track circuit including a track relay for each section, means effective to deenergize said signal control relay when the track relay for the first section becomes released by a train approaching the intersection, a normally deenergized stick relay, a timing device having an initial condition and an operated condition, means effective to initiate the operation of said timing device when the track relay for the first section becomes released provided said stick relay is then in its deenergized condition, means effective to energize said stick relay when said timing device attains its operated condition, means then effective to hold said stick relay in its energized condition as long as the track relay for said first section remains released, means effective to energize said signal control relay when said stick relay is in its energized condition provided said timing device is then in its initial condition, and means governed by the track relay for the second section for again deenergizing said signal control relay when such track relay becomes released.

7. In combination, a stretch of railway track including an intersection with a highway, a first track section and a second track section included in said stretch and successively occupied by a train approaching said intersection, a highway crossing signal located at said intersection, a normally energized signal control relay effective when deenergized to cause the operation of said signal, a track circuit including a track relay for each section, a normally deenergized stick relay, a timing device having an initial condition and an operated condition, means effective to initiate the operation of said timing device when the track relay for the first section becomes released provided said stick relay is then in its deenergized condition, means effective to energize said stick relay when said timing device attains its operated condition, means then eifective to hold said stick relay in its operated condition as long as the track relay for said first section remains released, a circuit for said signal control relay including a front contact of the track relay for the first section and a front contact of the track relay for the second section, and a branch path connected around the front contact of the track relay for said first section including a front contact of said stick relay and a contact closed only when said timing device is in its initial condition.

8. In combination, a stretch of railway track including an intersection with a highway, a first track section and a second track section included in said stretch and successively occupied by a train approaching said intersection, a highway crossing signal located at said intersection, a normally energized signal control relay effective when deenergized to cause the operation of said signal, a track circuit including a track relay for each section, a normally deenergized directional relay which becomes energized a predetermined interval of time after the track relay for the first section becomes released or when the track relay for the second section becomes released, means effective when said directional relay is in its energized condition to hold such relay in that condition as long as the track relay for the first section is released, means for deenergizing said signal control relay when the track relay for the first section becomes released provided said directional relay is then deenergized, and means for deenergizing said signal control relay when the track relay for the second section becomes released.

HARRY C. VANTASSEL. 

